Detectives from the Perth-based major crime squad travelled to Geraldton to begin an investigation into the woman’s death, while the police internal affairs unit began conducting a separate investigation into police conduct.

The WA Police union issued a statement saying it was “standing by” the police involved. “Our thoughts go out to the police officers involved and their families in this terrible circumstance,” union president Harry Arnott said.

It is the third fatal police shooting in WA in the past 12 months.

The Yamatji woman, with ties to the Mullewa community about 100km inland from Geraldton, had a seven-year-old child. Her foster mother travelled to Geraldton on Wednesday to learn what had happened.

It is the second death in police custody to rock the tight-knit Aboriginal community in Geraldton in five years. The Yamatji woman Ms Dhu, who died in Port Hedland in 2014, was raised in Geraldton and her grandmother and family still live there.

A recommendation from the royal commission into Aboriginal deaths in custody that police not be allowed to investigate police was built, in part, from the 1988 death in Geraldton police station of popular local footballer Edward Cameron.

Cameron’s death sparked a protest march through Geraldton.

Justice advocate Debbie Kilroy, who has been in contact with the woman’s family, has called for an independent investigation into the death.